Carburetor for gaseous fuel

ABSTRACT

A TUBULAR BODY HAVING A SIDE FUEL POST AND AN INLET AIR VALVE RESILIENTLY BIASED TOWARD A CLOSED POSITION AND OPERATIVE UNDER INTAKE VACUUM TO MAINTAIN SATISFACTORY FUEL-AIR MIXTURES THROUGHOUT A WIDE RANGE OF ENGINE SPEED.

Sept 5 1972 A. A. MANNlNo ErAl; 3,689,236

l CARBURETOR FOR GASEOUS FUEL Filed Jan. 13, 1971 United States Patent Omg@ Patented Sept. 5, 1972 3,689,236 CARBURETOR FOR GASEOUS FUEL Albert A. Mannino, 300 Chester Ave., and Charles N. Wolbert, 210 Moore St., both of Moorestown, NJ.

Filed Jan. 13, 1971, Ser. No. 106,142 Int. Cl. F02m 7/24, 17/00 U.S. Cl. 48--180 P 6 Claims ABSTRACT OF THE DISCLOSURE A tubular body having a side fuel port and an inlet air valve resiliently biased toward a closed position and operative under intake vacuum to maintain satisfactory fuel-air mixtures throughout a wide range of engine speed.

BACKGROUND OF THE INVENTION As is well known to those versed in the art, a wide variety of carburetors have been proposed for use with gaseous fuels. However, these prior gaseous fuel carburetors have not been entirely satisfactory, requiring relatively complex structures and consequent expensive manufacture and maintenance.

SUMMARY OF THE INVENTION Accordingly, it is an important object of the present invention to provide a carburetor for gaseous fuel which overcomes the above-mentioned difficulties, is extremely simple in structure, requiring relatively few parts for economy in manufacture, and being durable and reliable in operation so as to require a minimum of maintenance throughout a long useful life.

It is a further object of the present invention to provide a carburetor for gaseous fuel having the advantageous characteristics mentioned in the preceding paragraph, which is especially advantageous for use with small internal combustion engines, permitting of easy and accurate engine speed control, by which air pollution will be eiectively reduced, the engine oil maintained cleaner for less frequent change, and which greatly enhances expected engine life, the engine cost per hour of use being an irnportant aspect in the economics of small internal combustion engines.

Other objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings, which form a material part of this disclosure.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, which will be exemplified in the construction hereinafter described, and of which the scope will be indicated by the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top perspective view illustrating an internal combustion engine having a carburetor constructed in accordance with the teachings of the present invention.

FIG. 2 is a partial sectional elevational view taken generally along the line 2 2 of FIG. l, enlarged for clarity.

DESCRIPTION OF THE PREFERRED 'EMBODIMENT Referring now more particularly to the drawings, and specifically to FIG. 1 thereof, an internal combustion engine is there generally designated 10, which may be conventional in design, vincluding a cylinder block 11, fly wheel housing 12, and a fuel tank 13. In the instant embodiment, the fuel tank or container 13 may be a pressurized container of gaseous fuel, such as propane, butane or other such gaseous fuel.

The internal combustion engine 10 is provided with a carburetor, generally designated 15, constructed in accordance with the teachings of the present invention and connected to the fuel tank or container 13, as by a suitable fuel line 16. If desired, the carburetor 15 may be provided with an air filter of any suitable design, such iilter being omitted in the disclosure herein for clarity.

Considering the carburetor 1S in greater detail, the structure thereof includes an open ended, generally cylindrical or tubular member or body 18 having a longitudinally extending internal through bore or passageway 19. The carburetor body 18 is disposed generally vertically in the illustrated embodiment, and operates as a down-draft carburetor, but may be arranged as desired to accommodate various engine conditions.

One end of the tubular carburetor body 18, the lower end as seen in the illustrated embodiment, is connected by suitable conduit means 19, with the cylinder block fuel inlet or inlet manifold for delivering a fuel-air mixture, as will appear presently in greater detail. Provided on the upper end of tubular carburetor body 18, remote from the fuel-air conduit 20, is an air inlet valve, generally designated 22. The air inlet valve 22 includes a hollow body 23 engaged over the open upper end of carburetor tube 18, the valve body having an opening 24, say bounded by an annular flange 25 which engages conformably in the open upper end of carburetor tube 18. Thus, the interior of air inlet valve body 23 communicates through valve body opening 24 and annular flange 25 with the interior of carburetor tubular body 18 through the upper end thereof. The valve body 23 is preferably of a laterally increased or greater cross-sectional dimension than that of the tubular carburetor body 18, and is provided at its end remote from the tubular carburetor body with a generally flat end wall 26 disposed generally transversely of or normal t0 the longitudinal direction of fiuid flow through the interior hollow 19 of tubular body 18.

The transverse, generally flat outer end wall 26 of inlet valve body 22 may be provided with a central through opening 28, and a plurality of additional through openings or apertures 29 spaced about the central hole 28. Interiorly of the air inlet valve body 23, in generally parallel facing relation with the body end wall 26, is a generally fiat disc or closure plate 30, being provided centrally with a projecting lug or threaded pin 31 extending slidably outwardly through the central hole 28. An adjustable stop member or nut 32 may be threaded on the pin 31, and a coil compression spring 33 may be interposed between and having its opposite ends in bearing engagement with the inlet valve body wall 26 and the stop member 32. By this construction, the lgenerally flat plate or closure member 30 is yieldably resiliently urged by the spring 33 into closing relation with respect to the apertures 29.'v

It will now be appreciated that the air inlet valve 22 is of a one-way construction, permitting movement of air only inwardly into the carburetor body 18 through the upper carburetor end. Further, the opening of air inlet valve 22 is automatically varied by the manifold or inlet vacuum of the engine transmitted to the interior of the air inlet valve, so that a greater quantity or rate of flow of inlet air is achieved in accordance with the requirements of the engine, as determined by engine operation. Further, by reason of the laterally enlarged configuration of the air inlet valve body 23, it will be understood that upon increased movement of the closure member 30 downwardly, away from the wall 26, to further open the apertures 29, there is provided reduced restriction or resistance to the air ow. This assures an adequate supply of fuel mixture, as Well as a satisfactory ratio of fuel mixture throughout a wide range of operating conditions.

The fuel line 16 may extend from its end connection with the container 13 to connection to one side of the carburetor body 18, is in fluid communication through a side port 35 with the interior of the tubular carburetor body 18 medially between the ends thereof. That is, the tubular carburetor body 18 is provided with the gaseous fuel inlet port 35 on one side of the body spaced between the body ends, and the fuel line 16 is connected to the tubular carburetor body for uid communication through the port 35 with the interior of the tubular body. A fuel regulation valve 36 may be connected in the fuel line 16 for opening and closing the fuel line to its communication with the carburetor, and for also varying the rate of ow of gaseous fuel from the tank 13 to the carburetor.

From the foregoing, it is seen that the present invention provides a carburetor for gaseous fuel which is extremely simple in construction, capable of engine speed control over a wide range of operating conditions, and which otherwise fully accomplishes its intended objects.

In brief summary, it will be seen that operation of the gaseous fuel control valve 36, as by a remote operating member 37, will control the quantity or rate of ow of gaseous fuel to the engine. Upon an increase in fuel ilow to the engine, the engine tends to increase in speed, thereby drawing an additional quantity of air through the air inlet valve by increasing the opening of closure member 30. An equilibrium condition is quickly reached whereupon a satisfactory ratio of fuel to air is delivered to the engine for the desired speed and power requirements. Similarly, upon reduced opening of the fuel control valve 36, the engine tends to reduce its operating speed for reducing the inflow of air through air inlet valve, so that a satisfactory fuel-air mixture is rapidly reached according to the desired reduced motor speed and power requirements.

If desired, the carburetor tube 18 may be further provided with an escape or safety valve, say between the air inlet valve 22 and port 35, permitting the exit of gas to the atmosphere at a predetermined elevated pressure. This serves to prevent excessive gas pressure build-up in the carburetor, to avoid the possibility of explosion and an unduly rich fuel-air mixture. Also a pressure regulating or reducing valve may be provided in the fuel line 16 to permit of relatively high pressure gas storage in the container 13 and relatively low pressure gas delivery to the carburetor 15.

Although the present invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is understood that certain changes and modifications may be made within the spirit of the invention.

We claim:

1. A carburetor for gaseous fuel comprising an elongate tubular body having a longitudinal through passageway adapted to receive ambient air at one end and to deliver a fuel-air mixture at its other end, said body having a port extending through one side of said body, a conduit having one end connected to said one side of said body for communication through said port to the interior of said body, the other end of said conduit being adapted for connection to a source of gaseous fuel, an adjustable fuel valve in said conduit for varying the flow of gaseous fuel to said body to vary engine speed, and a one-way resiliently biased air inlet valve at said one end of said body for admitting air in relation to engine speed, to maintain satisfactory fuel-air mixtures at different speeds.

2. A carburetor for gaseous fuel according to claim 1, said air inlet valve comprising a wall having openings for communication between the exterior and interior of said body, a closure member on the inner side of said Wall in closing relation with said openings, mounting means mounting said closure member for movement inwardly away from said wall to open said openings, and spring means resiliently urging said closure member toward its closing relation, whereby engine intake vacuum serves to open the closure member as required by engine speed.

3. A carburetor for gaseous fuel according to claim 2, said wall and closure member being generally parallel and disposed generally transversely of the direction of fluid movement through said body, whereby increased closure member movement away from said wall effectively reduces restriction to iluid flow.

4. A carburetor for gaseous fuel according to claim 2, said mounting means comprising a pin extending from said closure member slidably through said wall.

5. A carburetor for gaseous fuel according to claim 4, said spring means comprising a coil compression spring circumposed about said pin extending from said wall having one end engaging said Wall, and an abutment on said pin in retaining engagement with the other end of said spring.

6. A carburetor for gaseous fuel according to claim 5, said wall and closure member being generally parallel and disposed generally transversely of the direction of uid movement through said body, said air inlet valve being configured so that increased closure member movement away from said wall reduces resistance to fluid ow.

References Cited UNITED STATES PATENTS 1,400,810 12/1921 Gaillard 48-180 1,623,721 4/1927 'Florey 48--180 2,223,919 12/1940- Oswald 48-180 S 2,613,658 10/1952 Coffey 48-180 X 3,034,492 5/ 1962 Harmon 48-180 UX 3,073,686 l/l963 Harris et al 48--180 3,395,899 8/1968 Kopa 48--180 X 3,512,511 5/1970 =Rapp0lt 48-180 X 3,528,787 9/1970 Hallberg 48-180 X 3,539,313 11/1970 PhippS 48-180 X MORRIS O. WOLK, Primary Examiner R. E. SERWIN, Assistant Examiner U.S.. C1. X.R. 48-180 C 

